Apparatus including electrochemical devices and heat exchanger

ABSTRACT

An apparatus can include a housing, a plurality of electrochemical devices disposed within the housing, and a heat exchanger disposed within the housing. The heat exchanger can be faced with an oxidant-containing gas outlet surface of at least one of the plurality of electrochemical devices. The electrochemical devices can include a stack of solid oxide fuel cells, a battery, or a solid oxide electrolyzer cell.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority under 35 U.S.C. § 119(e) to U.S.Provisional Patent Application No. 62/951,959, filed Dec. 20, 2019, byClaire LOE et al., entitled “APPARATUS INCLUDING ELECTROCHEMICAL DEVICESAND HEAT EXCHANGER,” which is assigned to the current assignees hereofand incorporated herein by reference in its entirety for all purposes.

FIELD OF THE DISCLOSURE

The following is directed to apparatus including a plurality ofelectrochemical devices and a heat exchanger.

DESCRIPTION OF THE RELATED ART

Solid oxide fuel cells (SOFC) are electrochemical devices that operateat high temperatures (e.g., 600° C. to 1000° C.). A hot box enclosing anSOFC stack can include insulation to maintain the fuel cells at thedesired operating temperatures. The heat generated by the fuel cells isused to maintain the temperature within the hot box. However,maintaining a uniform distribution of the temperature throughout the hotzone can be challenging both because the heat may be generatednon-uniformly and the incoming flows provide a cooling effect. Thus, ina well-insulated hot box, gas outlet faces can be significantly hotterthan gas inlet faces, which can cause undesired thermal gradients in thefuel cell stack leading to non-uniform current distribution, localthermal stresses, and performance degradation. This issue can bemagnified with state-of-the-art SOFC stacks formed with only ceramics(referred to as “all-ceramic stack” hereinafter), because components ofan all-ceramic stack have relatively low thermal conductivity, e.g., atleast 10 times lower, compared to those containing bulk metal componentscommonly used in fuel cells. Larger thermal gradients can be generatedwithin an all-ceramic stack, which can accelerate performancedegradation of the stack.

All-ceramic stacks also have advantages over metal-supported SOFC stacksand stacks having metal interconnects. For instance, all-ceramic stackscan be formed by co-sintering a plurality or an entire stack of fuelcells, which can simplify the manufacturing process and reduceassociated cost. Additionally, it is possible to obtain a tight match ofthermal expansion coefficients (CTEs) between components by carefullyselecting suitable materials, which helps to reduce the risk offormation of cracks during firing processes or operations, induced bythermal stress due to mismatched CTEs. Metals often have much higherCTEs compared to ceramic materials used in fuel cell stacks, renderingit difficult to match the CTEs of an adjacent ceramic component to themetal component. Furthermore, at solid oxide fuel cell operationtemperatures, metal surfaces tend to oxidize, which can increase thecontact resistance between the metal and adjacent ceramic component,resulting in degradation of electrochemical performance of fuel cells.Using surface coatings may help to reduce oxidation of metal surfaces,but it significantly increases the manufacturing cost.

The industry continues to demand fuel cells with improved performance,stability, and efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be better understood, and its numerousfeatures and advantages made apparent to those skilled in the art byreferencing the accompanying drawings.

FIG. 1 includes an illustration of a cross-sectional view of anapparatus according to an embodiment.

FIG. 2 includes an illustration of a perspective view of anelectrochemical device according to an embodiment.

FIG. 3 includes an illustration of a heat exchanger according to anembodiment.

FIGS. 4 to 10 include illustrations of exemplary heat exchangeraccording to embodiments herein.

FIG. 11 includes an illustration of a perspective view of a portion ofan apparatus according to an embodiment.

FIG. 12 includes an illustration of a perspective view of a heatexchanger according to another embodiment.

FIG. 13 includes an illustration of a cross-sectional view of anapparatus according to another embodiment.

FIG. 14 includes an illustration of another cross-sectional view of anapparatus according to an embodiment.

FIG. 15 includes an illustration of a cross-sectional view of a portionof an apparatus according to another embodiment.

FIG. 16 includes an illustration of a perspective view of a portion ofan apparatus according to still another embodiment.

FIGS. 17 to 20 include illustrations of manifolds according toembodiments.

FIGS. 21 and 22 include an illustration of top views of apparatusaccording to embodiments.

FIG. 23 includes an illustration of a manifold according to anembodiment.

FIGS. 24 to 25 include illustrations of top views of apparatus accordingto embodiments.

FIG. 26 includes an illustration of a manifold according to anotherembodiment.

FIGS. 27 to 29 include illustrations of pipes according to embodiments.

FIG. 30 includes an illustration of a pipe configuration according to anembodiment.

FIG. 31 includes an illustration of a pipe configuration according toanother embodiment.

Skilled artisans appreciate that elements in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the elements in the figures canbe exaggerated relative to other elements to help improve understandingof embodiments of the invention. The use of the same reference symbolsin different drawings indicates similar or identical items.

DETAILED DESCRIPTION

The following description in combination with the figures is provided toassist in understanding the teachings disclosed herein. The followingdiscussion will focus on specific implementations and embodiments of theteachings. This focus is provided to assist in describing the teachingsand should not be interpreted as a limitation on the scope orapplicability of the teachings.

As used herein, the terms “comprises,” “comprising,” “includes”,“including”, “has”, “having,” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of features is notnecessarily limited only to those features but can include otherfeatures not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive-or and not to an exclusive-or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

The use of “a” or “an” is employed to describe elements and componentsdescribed herein. This is done merely for convenience and to give ageneral sense of the scope of the invention. This description should beread to include one or at least one and the singular also includes theplural, or vice versa, unless it is clear that it is meant otherwise.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The materials, methods, andexamples are illustrative only and not intended to be limiting.

Embodiments herein relate to an apparatus including a housing enclosinga plurality of electrochemical devices and a heat exchanger arranged toheat cool inlet gas, such as an oxidant-containing inlet gas or a fuelinlet gas, before the inlet gas is transported to the plurality ofelectrochemical devices. In an embodiment, the apparatus may take theform of a hotbox. Particular embodiments relate to a 2.5 kW hotboxmodule. The apparatus of embodiments herein can accommodate gas flowdistributions for a plurality of electrochemical devices using adecreased number of piping connections and/or manifolds that can reducestructure complexity, provide a user-friendly assembly, and alsodecrease the risk of chromium poisoning due to reduced utilization ofmetal.

Referring to FIG. 1, a cross-sectional view of an apparatus 100according to an embodiment is illustrated. A plurality ofelectrochemical devices 102 and a heat exchanger 103 are disposed withinthe housing 101. The electrochemical device 102 can include a stack ofsolid oxide fuel cells, an electrolyzer, a hydrogen pump, an oxygenpump, a battery, or the like.

Briefly turning to FIG. 2, a perspective view of an exemplaryelectrochemical device, a stack of solid oxide fuel cell 200, isillustrated. The stack 200 includes a plurality of solid oxide fuelcells 202 separated by interconnect layers 208. A solid oxide fuel cell202 can include a cathode 203, an anode 205, and an electrolyte 204disposed between the cathode 203 and anode 205. The stack 200 can beformed utilizing suitable techniques and materials that are known in theart. In particular embodiments, the stack 200 can be formed with ceramicmaterials, and in more particular instances, the stack 200 can consistessentially of ceramic materials.

As further illustrated in FIG. 2, the cathode 203 and anode 205 can beporous. For instance, the cathode 203 can include gas channels extendingalong the length direction 232 of the solid oxide cell 202 to allowoxidant-containing gas to enter the cathode 203 via openings at one sidesurface of the cathode (not depicted) and exhaust to exit throughopenings at the opposite side surface of the cathode 203, such asopenings 210. The anode 205 can also include gas channels extending inthe width direction 234 of the solid oxide fuel cell 202. Fuel gas canenter the anode gas channels through openings at one side surface (notdepicted) and exhaust can exit through openings at the opposite sidesurfaces, such as openings 212. Accordingly, the stack 200 can have across flow configuration. Further, the stack 200 can include anoxidant-containing gas inlet surface (not depicted) opposite anoxidant-containing gas outlet surface 220 and a fuel gas inlet surface(not depicted) opposite the fuel gas outlet surface 222. As used herein,a gas inlet surface is intended to refer to a surface that receives thegas, and a gas outlet surface is intended to refer to a surface fromthat exhaust generated from the gas exits. An exemplary fuel gas caninclude hydrogen (e.g. pure or humidified), a mixture of 50% of hydrogenand 50% of nitrogen or a humidified mixture thereof, a reformate of amixture of CH₄, CO₂, CO, H₂, H₂O, or a hydrocarbon. An exemplaryoxidant-containing gas can include an oxygen-containing gas, such asair.

The stack 200 can have a certain dimension including a height 230,length 232, and width 234. In an embodiment, the height 230 can be in arange from 180 mm to 600 mm. In another embodiment, the width 234 can bein a range from at least 60 mm to at most 300 mm. In yet anotherembodiment, the length 232 can be in a range from at least 60 mm to atmost 300 mm or in a range from at least 60 mm to at most 280 mm. In someapplications, the width 234 can be essentially the same as the length232. A skilled artisan will appreciate any of the dimension of the stack200 can change to suit the power requirement of specific applications.

In a further embodiment, a coating may be applied to at least certainsurface areas to help reduce gas leakage from a component of the stack200, such as cathode 203 or anode 205. In an exemplary application, thecoating can include a glass material or a ceramic material. Forinstance, the coating can include BaO, Al₂O₃, SiO₂, or any combinationthereof. As further illustrated in FIG. 2, a current collector 201 canbe disposed on the stack 200.

In an embodiment, the plurality of electrochemical devices 102 can beadapted to operate at a relatively high temperature, such as in a rangeincluding at least 500° C. and at most 1000° C. For instance, theoperation temperature can be at least 650° C. or at least 750° C. or atleast 800° C.

Turning to FIG. 1, the heat exchanger 103 can be arranged to face thesurfaces 121 of the electrochemical devices 102. In an embodiment, atleast one of the surfaces 121 can be a gas outlet surface. In aparticular embodiment, at least one of the surfaces 121 can be anoxidant-containing gas outlet surface, such as the surface 220illustrated in FIG. 2. In a more particular embodiment, the surfaces 121are both oxidant-containing gas outlet surface. In another embodiment,the surfaces 121 can be fuel gas outlet surfaces, such as the surface222 illustrated in FIG. 2.

The heat exchanger 103 can include a gas inlet portion 131 that receivescool inlet gas, such as fuel gas or oxidant-containing gas having atemperature lower than a temperature of the electrochemical devices 102and at least one gas outlet portion. In an embodiment, the inlet gasentering the inlet portion 131 can have a temperature at least 50° C.less than the temperature of the surfaces 121. For instance, the inletgas temperature can be at least 100° C. or at least 150° C. or at least200° C. or at least 250° C. or at least 300° C. or at least 350° C. lessthan the temperature of the surfaces 121.

In the illustrated embodiment, the heat exchanger 103 includes a firstgas outlet portion 132 and a second gas outlet portion 133 from that theheated inlet gas can exit the heat exchanger 103. The heated inlet gascan be transported to the gas inlet surfaces of the electrochemicaldevices 102 through one or more pipes 134 that are directly orindirectly connected to the heat exchanger gas outlet portions 132 and133, respectively.

In a further embodiment, the heated inlet gas can be received byelectrochemical devices 102 at gas inlet surfaces opposite the surfaces121 via gas channel openings. Exhaust generated by electrochemicalreactions that take place in the electrochemical devices 102 can exitthe surfaces 121. Heat coming from the electrochemical devices 102 andtheir exhaust can be utilized by the heat exchanger 103 to continue toheat inlet gas. In an embodiment, heat can be transferred to the heatexchanger 103 via radiation and convection.

As illustrated in FIG. 1, the heat exchanger 103 can be disposed inparallel with and spaced apart from the surfaces 121. The heat exchanger103 can include a first branch 135 and a second branch 136 extending inopposite directions and in a serpentine shape. The heat exchanger 103can further include a total length L_(HEX) extending between the gasoutlet portions 132 and 133 in the direction of the length or the widthof the electrochemical devices 102, such as the length 234 or the width232 illustrated in FIG. 2.

Referring to FIG. 3, the heat exchanger 103 can have a height H_(HEX), afirst length L_(HEX1) and a second length L_(HEX2). In an embodiment,the height H_(HEX) may be less than the height of the electrochemicaldevices 102, such as the height 230. The length L_(HEX1) and L_(HEX2)may be similar to or less than the length or width of theelectrochemical devices 102. In another embodiment, the area A_(HEX)defined by the height H_(HEX) and the length L_(HEX1)(A_(HEX)=H_(HEX)×L_(HEX1)) or the height H_(HEX) and the length L_(HEX2)(A_(HEX)=H_(HEX)×L_(HEX2)) can be at least 25% of the surface area ofthe surface 121, such as at least 40%, at least 50%, at least 60%, or atleast 75% of the surface area of the surface 121. In another instance,the arear A_(HEX) may be at most 95% or at most 90% of the surface areaof the surface 121.

As illustrated in FIG. 1, portions close to the top and bottom of thesurfaces 121 are not faced with the heat exchanger 103. In anembodiment, the heat exchanger 103 can be positioned such that the areaA_(HEX) are directly faced with an area of the surface 121 that isbetween 10% and 90% of the height of the electrochemical devices 102,such as between 20% to 90% or between 20% to 80% or between 20% to 70%of the height of the electrochemical devices 102.

In another embodiment, the height H_(HEX) of the heat exchanger 103 canbe essentially the same or greater than the height of theelectrochemical devices 102. For instance, the height H_(HEX) can be atleast 100% of the height of the device 102, at least 110%, or at least120% of the height of the electrochemical devices 102. In anotherinstance, the height H_(HEX) may be at most 150% of the height of theelectrochemical devices 102.

In an embodiment, the heat exchanger 103 can be arranged such thatexhaust exiting the surfaces 121 can directly impinge on the heatexchanger 103 to facilitate improved heat transfer efficiency. Inanother embodiment, the inlet portions 135 and 136 can be faced with thehottest portions of the electrochemical devices 102. A skilled artisanwill appreciate a temperature gradient can be present in theelectrochemical devices. In applications that the electrochemicaldevices include stacks of solid oxide fuel cells 200, the hottest areascan be the corners formed by the oxidant-containing gas outlet surfacesand fuel gas outlet surfaces. The heat exchanger 103 can be positionedsuch that the inlet portions 135 and 136 can be as close as possible tothose corners. Accordingly, the inlet portions 135 and 136 can be distalto cooler areas of the electrochemical devices, such as the cornersformed by oxidant-containing gas inlet surfaces and fuel gas inletsurfaces of stacks 200. The outlet portions 132 and 133 can be adjacentto cooler areas and distal to hotter areas of the electrochemicaldevices 102. In yet another embodiment, the heat exchanger 103 can bepositioned such that the hottest area of the electrochemical devices canbe directly faced with the inlet portions 135 and 136 and such thatexhaust can directly impinge on the inlet portions 135 and 136.

FIGS. 4 to 8 include further illustrations of exemplary heat exchangersthat may be used alone or in combination in place of the heat exchanger103 in implementations. FIG. 4 illustrates a front perspective view of aheat exchanger 400 having a shape of a plate or box. Inlet gas can enterthe opening 402 and exit the outlet opening 404. The major surface 406of the heat exchanger 400 can be arranged to face the surfaces 121.

In FIG. 5, the heat exchanger 500 can include a single gas passage wayextending in a serpentine shape, an inlet opening 502, and an outletopening 504. In particular implementations, the inlet portion 520 can bedirectly faced with the hottest area of one of the electrochemicaldevices 121 and the outlet portion 510 may be faced with a cooler areaof the electrochemical devices 102. FIG. 6 includes an illustration ofanother heat exchanger 600 having a serpentine shape including a firstbranch 612 and a second branch 614 extending in opposite directions. Theheat exchanger 600 can be positioned in the similar manner as describedin embodiments herein with respect to the heat exchanger 103.

In an embodiment, any of the heat exchangers, such as 103, 400, 500,600, 700, and 800 can include baffles, fins, or a combination thereofinside the heat exchanger. For instance, the heat exchanger 700 includesbaffles 702, as illustrated in FIG. 7. FIG. 8 includes an illustrationof the heat exchanger 800 including baffles 812, 814, and 816 that arearranged differently from the baffles 702.

Portions of heat exchangers 900 and 1000 are illustrated in FIGS. 9 and10, respectively. The heat exchanger can include fins 902 extendingoutward from the wall 906 defining a flow path 904. The fins 1002 areshaped differently than the fins 902 and extending from the wall of theheat exchanger 1000 defining a flow path 1004. A skilled artisan willappreciate fins and baffles having various forms and shapes can besuitable for the heat exchanger of embodiments herein.

In an embodiment, the heat exchanger can include a particular materialthat can facilitate improved heat transfer efficiency. In an aspect, theheat exchanger can include a material having a particular emissivity tohelp improve absorption of radiated heat energy. For instance, suchmaterial can have an emissivity of at least 0.90 or at least 0.95. Asused herein, emissivity can be measured in accordance with ASTM E408-13.In another aspect, the heat exchanger can have a black outer surface. Ina further aspect, the heat exchanger may be formed with a materialhaving a relatively lower emissivity and coated with another materialhaving the desired emissivity. In yet another aspect, the heat exchangercan include a heat-resistant, oxidation-resistant, or acorrosion-resistant material. For example, the heat exchanger caninclude an alumina scale-forming material, an interconnect material, orany combination thereof. An exemplary alumina scale-forming material caninclude a ferritic alloy, such as an iron-chromium-aluminum alloy (e.g.,Kanthal APM™ and APMT™, Nisshin Steel NCA-1™), anickel-chromium-aluminum-iron alloy (e.g., Haynes® 214®), or ahigh-carbon nickel-chromium-iron alloy (e.g., Nicrofer® 6025 HT-Alloy602 CA). An exemplary interconnect material can include a metallicinterconnect material, such as an iron-chromium alloy (e.g., Hitachi®ZMG232G10®, Crofer 22® APU), or a high temperature stainless steel(e.g., Crofer® 22H, Sanergy HT 441, E-Brite®). In a particular example,a coating material can be applied to the surface of the heat exchangerincluding a metallic interconnect material. The coating can include aglass material, an oxide, such as alumina and manganese cobalt oxide orthe like, or any combination thereof. Another example of an interconnectmaterial can include a ceramic material known in the art. In anotherinstance, the heat exchanger can include an oxide, such as berylliumoxide, a carbide (e.g., SiC), a nitride, such as aluminum nitride. Inyet another example, the heat exchanger can include a superalloy, suchas a nickel-chromium based superalloy (e.g., Inconel® 600, 601, or 625),a nickel-based steel alloy (e.g., Hastalloy®), a nickel-based superalloy(e.g., Waspaloy®, Rene® 41, or Incoloy®), or any combination thereof.

In an embodiment, the apparatus can include at least 2, at least 3, atleast 4, at least 5, at least 6, at least 7, at least 8, or at least 9electrochemical devices. In an embodiment, the plurality ofelectrochemical devices may be arranged in a single row or a singlecolumn, as illustrated in FIG. 1. In another embodiment, the pluralityof electrochemical devices may be arranged in rows and columns.

In a particular embodiment, the apparatus may include at least 4electrochemical devices. In a particular example of an apparatus having4 electrochemical devices, the first and second electrochemical devicesmay be positioned as electrochemical devices 102, as illustrated in FIG.1, the third and further electrochemical devices may be positioned toform a 2×2 grid. The heat exchanger 103 can extend between the first andthird electrochemical devices and between the second and furtherelectrochemical devices. Particularly, the heat exchanger 103 can befaced with gas outlet surfaces of all the electrochemical devices. Forinstance, the heat exchanger 103 can be disposed between theoxidant-containing gas outlet surfaces of the first and thirdelectrochemical devices and between the oxidant-containing gas outletsurfaces of the second and fourth electrochemical devices. In anotherinstance, the heat exchanger 103 can be faced with all the fuel gasoutlet surfaces of the electrochemical devices.

FIG. 11 includes an illustration of a portion of the apparatus 1100including 4 electrochemical devices according to a particularembodiment. One of the electrochemical devices is not illustrated tofurther aid understanding of the structure of the apparatus 1100.

The apparatus 1100 can include a housing 1111 enclosing theelectrochemical devices arranged in a grid. A skilled artisan willappreciate only a portion of the housing 1111 is illustrated in FIG. 11.The housing 1111 can be similar to the housing 101. The electrochemicaldevices can be positioned such that the oxidant-containing gas outletsurfaces of the electrochemical devices 1102 and 1103 are face-to-faceand the oxidant-containing gas outlet surfaces of the electrochemicaldevices 1101 and 1104 (not depicted) are face-to-face.

The apparatus 1100 can include a central oxidant-containing outlet gaschamber 1108 that can be in fluid communication with each ofelectrochemical devices 1101 to 1104. As illustrated, theoxidant-containing outlet gas chamber 1108 can be positioned between theelectrochemical devices 1102 and 1103 and between the electrochemicaldevices 1101 and 1104. The heat exchanger 1105 can be disposed withinthe oxidant-containing outlet gas chamber 1108.

In particular implementations, the oxidant-containing outlet gas chamber1108 can be defined by the oxidant-containing gas outlet surfaces 1106,side walls 1129 of manifolds 1128, top structure components 1110, bottomstructure components 1190, and the housing 1111. The structurecomponents 1110 and 1190 can be in the form of metal or ceramic boxes orblocks. In particular embodiments, oxidant-containing outlet gas exitingoxidant-containing outlet surfaces 1106 can directly enter theoxidant-containing outlet gas chamber 1108. The oxidant-containingoutlet gas chamber 1108 can be in fluid communication with at least oneoutlet gas pipe for transporting exhaust out of the chamber. As furtherillustrated in FIG. 11, the bottom structure component 1190 can have anopening 1151, and a gas outlet pipe 1152 can be connected to the bottomcomponent 1190 at the opening 1151. Exhaust can exit the opening 1151and be transported by the gas outlet pipe 1152.

As illustrated, the heat exchanger 1105 extends between theoxidant-containing gas outlet surfaces 1106 of the electrochemicaldevices 1101 to 1104. Accordingly, the heat exchanger 1105 is directlyfaced with 4 oxidant-containing gas outlet surfaces. The heat exchanger1105 can have any of the features described in embodiments herein withrespect to heat exchangers.

A particular embodiment of the heat exchanger 1105 is illustrated inFIG. 12. The heat exchanger 1105 can be connected to an inlet gas pipe1153 that can be configured to transport cold oxidant-containing gas tothe heat exchanger 1105. As used herein, the cold oxidant-containing gasis intended to refer to oxidant-containing inlet gas that has not beenpreheated to up to the temperature of electrochemical devices 1101 to1104 before reaching the heat exchanger 1105. The inlet portions 1171and 1172 can be adjacent and faced with hottest areas of theelectrochemical devices 1102 and 1103 and 1101 and 1104, respectively.The outlet portions 1173 and 1174 can be connected to gas pipes 1154 and1155, respectively, for transporting heated inlet gas to theelectrochemical devices 1101 to 1104.

Referring to FIG. 11, the apparatus 1100 can include a firstoxidant-containing gas inlet chamber 1109 in fluid communication withthe electrochemical devices 1101 and 1103 and a secondoxidant-containing gas inlet chamber 1109 in fluid communication withthe electrochemical devices 1102 and 1104. The oxidant-containing gasinlet chamber 1109 can be defined by structure components 1110,oxidant-containing gas inlet surfaces 1107, side walls 1130 of themanifolds 1112, and the housing 1111.

In an embodiment, the gas pipe 1154 can be in fluid communication withthe first oxidant-containing gas inlet chamber 1109. For instance,heated inlet gas can be transported by the gas pipe 1154 to the firstoxidant-containing gas inlet chamber 1109, enter oxidant-containing gaschannels via openings at the oxidant-containing inlet gas surfaces 1107,and be utilized by the electrochemical devices 1101 and 1103. Similarly,the gas pipe 1155 can be in fluid communication with the secondoxidant-containing gas inlet chamber 1109, and heated inlet gas can betransported by the gas pipe 1155 to the second oxidant-containing gasinlet chamber 1109 and utilized by the electrochemical devices 1102 and1104.

Referring to FIG. 13, a cross section of the apparatus 1100 isillustrated. The oxidant-containing gas inlet surfaces 1107 can be opento the oxidant-containing gas inlet chamber 1109. The gas pipe 1154 (or1155) can be connected to a bottom structure component 1113 fortransportation of heated inlet gas to the oxidant-containing gas inletchamber 1109. As illustrated, the gas pipe 1154 (or 1155) may passthrough the bottom structure component 1113 and extend into theoxidant-containing gas inlet chamber 1109. In a particularimplementation, only one gas pipe (e.g., 1154 or 1155) for transportingheated oxidant-containing inlet gas is connected to the inlet gaschamber 1109.

The central heat exchanger 1108 can be in fluid communication with bothoxidant-containing gas inlet chambers 1109 via gas pipes 1154 and 1155.Further, the heat exchanger 1108 can be in fluid communication with eachof the electrochemical devices 1101 to 1104.

Referring to FIG. 11, the apparatus 1100 can include a first manifold1128 disposed between electrochemical devices 1102 and 1104. The firstmanifold 1128 can be attached to the two electrochemical devices.Particularly, the first manifold 1128 can be between fuel gas outletsurfaces of the electrochemical devices 1102 and 1104. The apparatus1100 can further include a first fuel gas outlet chamber 1131 defined bythe first manifold 1128 and fuel gas outlet surfaces of theelectrochemical devices 1102 and 1104. Similarly, the apparatus 1100 canfurther include a second fuel gas outlet manifold 1128 and a second fuelgas outlet chamber 1131 between the fuel gas outlet surfaces of theelectrochemical devices 1101 and 1103. The manifolds 1128 are the fuelgas outlet manifolds. As illustrated, the first and second fuel gasoutlet chambers 1131 is separated by the central oxidant-containing gasoutlet chamber 1108.

In a particular embodiment, a heat exchanger 1125 can be disposed withinat least one of the fuel gas outlet chambers 1131. In more particularimplementations, the apparatus 1100 can include a heat exchanger 1125disposed within each of the fuel gas outlet chambers 1131. The heatexchanger 1125 can be configured to absorb heat generated by theelectrochemical devices 1101 to 1104 and fuel outlet gas via radiationand convection. Further, the heat exchanger 1125 can be adapted to heatfuel inlet gas. In an embodiment, the heat exchanger 1125 can includeany of the features described with respect to other heat exchangers.

In another embodiment, at least one of the heat exchangers 1125 caninclude a reformer, a vaporizer, or a combination thereof. Referring toFIG. 14, a cross section of the apparatus 1100 is illustrated. A heatexchanger 1125 is disposed within each of the fuel gas outlet chambers1131 that are partially defined by the manifolds 1128. Each of the heatexchangers 1125 can include a reformer, be connected to a pipe 1134 thatis adapted to transport cool fuel gas to the heat exchanger 1125 andconnected to a pipe 1135 that is adapted to transport heated fuel inletgas from the heat exchanger 1125.

In an example, cool fuel inlet gas can first enter the reformer, heatedby the heat exchanger 1125, and exit the heat exchanger 1125 via thepipe 1135. In an embodiment, each of the pipes 1135 and heat exchangers1125 can be in fluid communication with at least one of theelectrochemical devices 1101 to 1104. In a particular instance, at leastone of the heat exchangers 1125 can be in fluid communication with aplurality of electrochemical devices via one of the pipes 1135. In theillustrated embodiment, the heat exchangers 1125 disposed in the fueloutlet chamber between the electrochemical devices 1101 and 1103 can bein fluid communication with the electrochemical devices 1101 and 1103and the other heat exchanger 1125 can be in fluid communication with theelectrochemical devices 1102 and 1104.

Each fuel gas outlet chamber 1131 can be connected to a pipe 1136 thatis adapted to transport fuel outlet gas. In a particular implementation,the pipes 1136 may be joined to form a main fuel outlet gas pipe.

Referring to FIG. 11, the apparatus 1100 can include a plurality of fuelinlet gas manifold. As illustrated in FIGS. 11 and 13, a fuel inlet gasmanifold 1127 can be attached to each of the electrochemical devices1101 to 1103. In an embodiment, the electrochemical device 1104 can beattached to a separate fuel inlet gas manifold 1127. The fuel gas inletsurface and the attached manifold 1127 of each electrochemical devicecan define a fuel gas inlet chamber. Each fuel gas inlet chamber can bein fluid communication with one of the heat exchangers 1125. Asillustrated, fuel inlet gas manifold 1127 and outlet manifold 1128 areexternal to the electrochemical devices 1101 and 1104.

FIG. 15 includes a cross-sectional illustration of a portion of theapparatus 1100 including a fuel gas inlet manifold 1127 attached to thefuel gas inlet surface of the electrochemical device 1101. A pipe 1135can be connected to the manifold 1127 to provide heated fuel inlet gasto the electrochemical device 1101. Heated fuel inlet gas can enter thefuel inlet gas chamber and fuel gas channel openings at the fuel gasinlet surface and be utilized by the electrochemical device 1101. Fuelinlet gas distribution can be implemented in the similar manner for theelectrochemical devices 1102 to 1104.

As illustrated, the apparatus 1100 may not include an oxidant-containinggas inlet or outlet manifold. A skilled artisan will appreciate anoxidant-containing gas inlet and/or outlet manifold can be implementedin the apparatus 1100, such as in a similar manner to the fuel gas inletand/or outlet manifold.

FIG. 16 includes an illustration of a portion of an apparatus 1600including 4 electrochemical devices 1601 arranged in a grid and a heatexchanger 1615 disposed within a central oxidant-containing gas outletchamber 1603. The fuel outlet gas manifolds 1605 are each disposedbetween two of the electrochemical devices 1601. As illustrated, theapparatus 1600 is similar to the apparatus 1100, except that a fuelinlet gas manifold 1606 is attached to two of the electrochemicaldevices 1601.

As further illustrated, a pipe 1607 is connected to the piping system1608 of the fuel inlet gas manifold 1606. The pipe 1607 can be adaptedto transport heated fuel inlet gas and in fluid communication with aheat exchanger (not depicted) disposed within one of the fuel outlet gasmanifold 1605. Heated fuel inlet gas can be distributed through thepiping system 1608 to the electrochemical devices 1601.

Referring to FIG. 17, a perspective view of the inside of the manifold1606 of FIG. 16 is illustrated. The manifold can include a plurality ofslits 1702 at the top surface 1705 of the manifold 1606. In someimplementations, the slits 1702 can extend along the major outer surface1706 (FIG. 16) to reach the bottom surface 1709 of the manifold 1606.The slits can help block gas flow from oxidant-containing gas inletand/or outlet surfaces of the electrochemical devices 1601. The manifold1606 can further include a lip 1703 to receive the electrochemicaldevice 1601. An exemplary lip can include an indent. The lip 1703 canallow the electrochemical device 1601 to rest against the manifold 1606providing additional sealing and stability. The holes 1704 canfacilitate inlet gas distribution. In some instances, the manifold 1606may include tubes in place of or in addition to the holes 1704. Themanifold 1606 can further include chambers 1707 to facilitate inlet gasdistribution. The chambers 1707 can form gas inlet chambers when themanifold is attached to electrochemical devices 1601.

FIG. 18 includes an illustration of another manifold 1800 including asingle chamber 1802 and tubes 1801 to facilitate inlet gas distribution.The manifold 1800 can also include slits 1702 and/or lip 1703. In anembodiment, the manifolds 1127 can include any of the features of themanifold 1800. Alternatively, the manifold 1127 can be similar to themanifold 1900 illustrated in FIG. 19. A plurality of slots 1902 insidethe chamber 1903 can facilitate even inlet gas distribution.

FIG. 20 includes an illustration of a manifold 2000 including an opening2002 at the bottom to allow fluid to pass through. In some instances,the opening 2002 may be replaced by a tube. In an embodiment, thecentral fuel gas outlet manifold 1128 illustrated in FIGS. 11 and/or1605 illustrated in FIG. 16 can be similar to the manifold 2000.

In an embodiment, the manifold can include a refractory material, suchas metal or ceramic material to facilitate inlet and outlet gasdistribution.

FIGS. 21 to 24 include illustrations of examples of the apparatusaccording to embodiments herein. FIG. 21 illustrates an apparatus 2100including a housing 2101 enclosing a plurality of electrochemicaldevices 2102 and a central oxidant-containing gas inlet chamber 2105that is in fluid communication with each of the electrochemical devices2102. The apparatus 2100 can further include a first heat exchanger 2103disposed within a first oxidant-containing gas outlet chamber 2104 and asecond heat exchanger 2103 positioned within the secondoxidant-containing gas outlet chamber 2104. Each heat exchanger 2103 canbe configured to heat oxidant-containing inlet gas, as described inembodiments with respect to heat exchangers 103 or 1105, and in fluidcommunication with the oxidant-containing gas inlet chamber 2105.Accordingly, each heat exchanger 2103 can be in fluid communication withat least one or at least two or all of the electrochemical devices 2102.

The apparatus 2100 can further include a plurality of fuel gas inletmanifolds 2106. Each manifold 2106 is disposed between and attached tothe fuel gas inlet surfaces of two of the electrochemical devices 2102.The fuel gas outlet surface of each electrochemical device 2102 isattached to a fuel gas outlet manifold 2108. In an embodiment, at leastone of the fuel gas outlet manifolds 2108 can enclose a heat exchanger,similar to the heat exchanger 1125, that is configured to heat fuelinlet gas and be in fluid communication with at least one or at leasttwo of the electrochemical devices 2102. In an embodiment, at least oneof fuel gas outlet manifolds 2108 can include a reformer, a vaporizer,or a combination thereof. As illustrated, the apparatus 2100 can includean arrangement including at least two electrochemical devices 2102alternating with manifolds 2106 and 2108.

FIG. 22 includes an illustration of an apparatus 2200 including acentral oxidant-containing gas outlet chamber 2205, a heat exchanger2203 disposed within the oxidant-containing gas outlet chamber 2205, anda plurality of oxidant-containing gas inlet chambers 2204. The heatexchanger may include a single flow path in the direction 2220.

The apparatus 2200 can include a fuel gas inlet manifold 2206 attachedto the electrochemical devices S1 and S3. A first fuel gas outletmanifold 2208 can be disposed between the electrochemical devices S1 andS2, and a second fuel gas outlet manifold 2208 can be disposed betweenthe electrochemical devices S3 and S4. In a particular embodiment, thefirst manifold 2208 can define a chamber that is fluid communicationwith the fuel gas outlet surface of the device S1 and with the fuel gasinlet surface of the device S2, and the second manifold 2208 can definea chamber that is fluid communication with the fuel gas outlet surfaceof the device S3 and with the fuel gas inlet surface of the device S4.Fuel outlet gas exiting the electrochemical device S1 can directly enterand serve as fuel inlet gas for the electrochemical device S2.Similarly, fuel outlet gas exiting the electrochemical device S3 can bedirectly utilized as fuel inlet gas for the electrochemical device S4.FIG. 23 includes an illustration of the fuel gas outlet manifold 2208including a central opening 2240 to allow fuel outlet gas exitingelectrochemical devices S1 and S3 to pass through. In a particularinstance, the manifold 2208 can be in the shape of a frame.

The apparatus 2200 can further include fuel gas outlet manifold 2209attached to fuel gas outlet surfaces of the electrochemical devices S2and S4.

FIG. 24 includes an illustration of an apparatus 2400 including aplurality of electrochemical devices 2401 to 2404 arranged in a row. Theapparatus 2400 includes a plurality of oxidant-containing gas outletchambers 2405 and 2406 alternating with a plurality ofoxidant-containing gas inlet chambers 2408 to 2410. Particularly, theoxidant-containing gas outlet chambers 2405 and 2406 are disposedbetween electrochemical devices, such as between 2404 and 2403 andbetween 2402 and 2401, respectively. Heat exchangers 2407 are disposedwithin the oxidant-containing gas outlet chambers 2405 and 2406 andconfigured to heat oxidant-containing inlet gas. The first heatexchanger 2407 disposed between the devices 2403 and 2404 can be influid communication with the oxidant-containing gas inlet chambers 2408and 2409 and with the devices 2402, 2403 and 2404. The second heatexchanger 2407 disposed between the devices 2402 and 2401 can be influid communication with the oxidant-containing gas inlet chambers 2409and 2410 and with the devices 2401, 2402, and 2403. For instance, heatedoxidant-containing inlet gas can be transported from the heat exchanger2407 and to oxidant-containing inlet chambers 2408 and 2409 and utilizedby the electrochemical devices 2404 and 2403. The heat exchanger 2407can include any of the features described with respect to the heatexchanger 103 and/or 1105.

Each electrochemical device 2401 to 2404 is attached to an individualfuel gas outlet manifold at the fuel gas outlet surface and a fuel gasinlet manifold at the fuel gas inlet surface. Alternatively, a manifoldthat can accommodate two electrochemical devices can be utilized as aninlet and/or outlet manifold, such as the manifold illustrated in FIG.17. The apparatus further includes a reformer 2418 disposed in theinsulation 2419 disposed adjacent the fuel gas outlet manifolds. Thefuel gas outlet manifolds can optionally enclose one or more heatexchangers that can be adapted to heat fuel inlet gas.

FIG. 25 includes an illustration of an apparatus 2500 including aplurality of electrochemical devices 2501 to 2504 arranged in a row, anoxidant-containing gas outlet chamber 2505 disposed at one side of therow, and an oxidant-containing gas inlet chamber 2506 disposed at theother side of the row. A heat exchanger 2507 similar to the heatexchanger 103 and/or 1105 is disposed within the oxidant-containing gasoutlet chamber 2505. The heat exchanger 2507 can be configured to heatoxidant-containing inlet gas and in fluid communication with theoxidant-containing inlet chamber and with each of the electrochemicaldevices 2501 to 2504.

The apparatus 2500 further includes a reformer 2518 disposed in theinsulation 2519 placed adjacent the oxidant-containing gas outletchamber 2505.

The apparatus 2500 also includes a plurality of fuel gas inlet manifolds2508 and 2509 and a plurality of fuel gas outlet manifolds 2510, 2512,and 2514 alternating with the fuel gas inlet manifolds 2508 and 2509.The fuel gas outlet manifold 2512 is deposed between electrochemicaldevices 2502 and 2503. In an embodiment, a heat exchanger similar to theheat exchanger 1125 can be disposed within the fuel gas outlet chambercontained by the manifold 2512 and in fluid communication with the fuelgas inlet manifolds 2508 and 2509. For instance, heated fuel inlet gascan be transported from the heat exchanger contained within the manifold2512 to the piping system of inlet manifolds 2508 and 2509 and utilizedby electrochemical devices 2501, 2502, 2503, and/or 2504. In anembodiment, the inlet manifolds 2508 and 2509 can be similar to themanifold 2600 illustrated in FIG. 26. The manifold 2600 can include achamber 2602, openings 2604 and tubes 2606 for inlet gas distribution.In a further embodiment, the fuel gas outlet manifolds 2510 and 2514 mayoptionally enclose a heat exchanger similar to the heat exchanger 1125that can be in fluid communication with the fuel gas inlet manifold 2508and 2509, respectively.

In an embodiment, gas pipes may include features that can facilitateeven inlet gas distribution. For instance, FIG. 27 includes anillustration of a pipe 2700 that may be suitable for transporting inletgas to individual electrochemical devices. The pipe 2700 can includebranches 2702, 2704, and 2706, extending away from the main flow path2701. In an embodiment, the branches can extend toward the respectivegas inlet surfaces of electrochemical devices. In an exemplaryimplementation, the pipe 2700 may be in fluid communication with theheat exchanger 2507 and configured to transport heatedoxidant-containing inlet gas to electrochemical devices 2501 to 2504. Inanother instance, the pipe 2700 can be configured to transport fuelinlet gas to fuel inlet manifolds. As inlet gas reaches the branch 2702first, increasing the diameter of the branch 2704 and further increasingthe diameter of the branch 2706 can facilitate equal gas distribution bythe branches 2702, 2704, and 2706. As illustrated, D₂₇₀₂<D₂₇₀₄<D₂₇₀₆.

FIG. 28 includes an illustration of a pipe 2800 including branches 2802,2804, 2806, and 2808, and a gas chamber 2809. The chamber 2809 can helpdecrease the velocity of the gas flow and thus, can facilitate evendistribution of inlet gas by the branches.

In FIG. 29, the pipe 2900 can include a flow path 2901 and branches2902, 2904, 2906, and 2908. As illustrated, each branch can include anecking 2910 extending into the flow path of the branch. The necking canhelp control the flow through each pipe branch. In an embodiment, notall the branches have the necking 2910. For instance, the necking 2910may be present in branches that are likely to have faster flow comparedto others.

In embodiments, the gas chamber 2809 illustrated in FIG. 28 can take theform of the gas chamber 3001 illustrated in FIG. 30. The gas chamber3001 has a central opening 3003 at the bottom of the chamber connectedto the pipe 3020 through which an inlet gas can enter the chamber 3001.The chamber 3001 further includes a plurality of side openings 3002connected to branches 3010 for transporting the inlet gas toelectrochemical devices (not depicted). In a particular embodiment, asillustrated in FIG. 31, the chamber 3001 and at least a portion of eachof the branches 3010 can be positioned within a bottom structurecomponent 3101. In an embodiment, the bottom structure component 3101can be similar to the component 1113 illustrated in FIG. 13. Thebranches 3010 can be connected to gas inlet chambers disclosed inembodiments herein, such as the gas inlet chamber 1109 illustrated inFIG. 11, and/or a gas inlet manifold, such as the fuel inlet manifold1127 illustrated in FIG. 11. In an example, the branches 3010 may beconnected to the bottom of an inlet gas chamber or manifold.

In an embodiment, components of the apparatus can be attached viacompression. In an embodiment, compression can be exerted by acompression system external to the housing. In another embodiment,compression can be exerted via independent springs, a band, a cable, aratchet, leaf springs, conical spring washers, clamps, weld, or anycombination thereof. Referring to FIGS. 1, 13, 22, 24, and 25,compression can be applied to attach manifolds to the electrochemicaldevices. As illustrated in FIG. 21, the apparatus 2100 can include atleast two electrochemical devices and at least 3 manifolds that arecompressed in series. Referring to FIG. 22, a single compression systemmay be used to compress in the direction 2230 and 2240 the fuel outletgas manifold 2209 and fuel inlet gas manifold 2210, respectively. As aresult, the apparatus 2200 can include a plurality of the arrangementscompressed in parallel. For instance, each arrangement can includemanifolds alternating with electrochemical devices that are compressedin series. As illustrated in FIG. 25, the apparatus 2500 can include asingle arrangement including alternating electrochemical devices andmanifolds that are compressed in series by applying compression 2530 and2531.

In an embodiment, compression can be transferred to the manifold,electrochemical devices, or a combination thereof via an insulationcomponent. Referring to FIG. 24, individual compression 2430 and 2431can be applied through insulation 2419 to fuel gas inlet and outletmanifolds attached to each electrochemical device. Further referring toFIG. 22, compression can be applied through the insulation components2210 to the fuel inlet gas manifold 2206 and outlet gas manifold 2209.In an example, the insulation component can include metal, refractorymaterial, or a combination thereof. In further embodiments, attachmentof an electrochemical device to an inlet and/or outlet manifold may befacilities by a gasket placed there between.

Many different aspects and embodiments are possible. Some of thoseaspects and embodiments are described herein. After reading thisspecification, skilled artisans will appreciate that those aspects andembodiments are only illustrative and do not limit the scope of thepresent invention. Embodiments may be in accordance with any one or moreof the embodiments as listed below.

Embodiments

Embodiment 1. An apparatus, comprising:

a housing;

a plurality of electrochemical devices disposed within the housing; and

a heat exchanger disposed within the housing and faced with anoxidant-containing gas outlet surface of at least one of the pluralityof electrochemical devices.

Embodiment 2. An apparatus, comprising:

a housing; and

a plurality of electrochemical devices disposed within the housing,wherein the plurality of electrochemical devices comprise a first andsecond electrochemical devices,

wherein one heat exchanger is disposed between the first and secondelectrochemical devices.

Embodiment 3. The apparatus of embodiment 2, wherein the heat exchangeris faced with a gas outlet surface of at least one of the first andsecond electrochemical devices.

Embodiment 4. The apparatus of any one of embodiments 2 to 3, whereinthe heat exchanger is faced with an oxidant-containing gas outletsurface of at least one of the first and second electrochemical devices.

Embodiment 5. The apparatus of embodiment 1, wherein the plurality ofelectrochemical devices comprise a first and second electrochemicaldevices, and wherein the heat exchanger is faced with anoxidant-containing gas outlet surface of the first electrochemicaldevices and an oxidant-containing gas outlet surface of the secondelectrochemical device.

Embodiment 6. The apparatus of any one of embodiments 2 to 5, whereinthe heat exchanger is disposed between an oxidant-containing gas outletsurface of the first electrochemical device and an oxidant-containinggas outlet surface of the second electrochemical device.

Embodiment 7. The apparatus of any one of embodiments 1 to 6, furthercomprising an oxidant-containing gas outlet chamber enclosed in thehousing, wherein the oxidant-containing gas outlet chamber is in fluidcommunication with at least one of the first and second electrochemicaldevices, and wherein the heat exchanger is disposed within theoxidant-containing gas outlet chamber.

Embodiment 8. The apparatus of embodiment 7, wherein theoxidant-containing gas outlet chamber is in fluid communication with atleast two of the plurality of electrochemical devices.

Embodiment 9. The apparatus of embodiment 7 or 8, wherein at least someof the plurality of electrochemical devices are arranged in a row,wherein the oxidant-containing gas outlet chamber is disposed on oneside of the row and in fluid communication with an oxidant-containinggas outlet surface of each electrochemical device in the row.

Embodiment 10. The apparatus of embodiment 7 or 8, wherein theoxidant-containing gas outlet chamber is disposed between at least twoof the plurality of electrochemical devices.

Embodiment 11. The apparatus of any one of embodiments 7 to 10, whereinthe plurality of electrochemical devices are arranged in rows andcolumns, wherein the oxidant-containing gas outlet chamber is disposedbetween and in fluid communication with electrochemical devices inadjacent rows or in adjacent columns.

Embodiment 12. The apparatus of any one of embodiments 1 to 11, whereinthe apparatus comprises:

a first electrochemical device, a second electrochemical device, a thirdelectrochemical device, and a fourth electrochemical device arranged ina grid; and

a central oxidant-containing gas outlet chamber in fluid communicationwith each of the first, second, third, and fourth electrochemicaldevices.

Embodiment 13. The apparatus of embodiment 12, further comprising:

a first fuel gas outlet chamber disposed between and in fluidcommunication with the first and second electrochemical devices; and

a second fuel gas outlet chamber disposed between and in fluidcommunication with the third and fourth electrochemical devices,

wherein the first and second fuel gas outlet chamber is separated by thecentral oxidant-containing gas outlet chamber.

Embodiment 14. The apparatus of embodiment 12 or 13, further comprising:

a first oxidant-containing gas inlet chamber in fluid communication withthe first and second electrochemical devices; and

a second oxidant-containing gas inlet chamber in fluid communicationwith the third and fourth electrochemical devices.

Embodiment 15. The apparatus of any one of embodiments 12 to 14, whereinthe heat exchanger is disposed within the central oxidant-containing gasoutlet chamber and faced with an oxidant-containing gas outlet surfaceof each of the first, second, third, and fourth electrochemical devices.

Embodiment 16. The apparatus of any one of embodiments 12 to 15, whereinthe heat exchanger is disposed such that a gas inlet portion of the heatexchanger is adjacent to a surface portion of the oxidant-containing gasoutlet surface has a higher temperature than the remainder of thatsurface for each of the first, second, third, and fourth electrochemicaldevices.

Embodiment 17. The apparatus of any one of embodiments 12 to 16, whereinthe heat exchanger is disposed such that a gas inlet portion of the heatexchanger is closer to a corner defined by the oxidant-containing gasoutlet surface and a fuel gas outlet surface than a corner defined bythe oxidant-containing gas outlet surface and a fuel gas inlet surfaceof each of the first, second, third, and fourth electrochemical devices.

Embodiment 18. The apparatus of any one of embodiments 12 to 17, whereinthe heat exchanger comprises a first branch and a second branchextending in different directions.

Embodiment 19. The apparatus of embodiment 18, wherein the first branchextends between the oxidant-containing gas outlet surfaces of the firstand third electrochemical devices, wherein the first branch is coupledto one of the first oxidant-containing gas inlet chambers or the secondoxidant-containing gas inlet chambers.

Embodiment 20. The apparatus of embodiment 18 or 19, wherein the secondbranch extends between the oxidant-containing gas outlet surfaces of thesecond and fourth electrochemical devices, wherein the second branch iscoupled to the other one of the first oxidant-containing gas inlet orthe second oxidant-containing gas inlet chambers.

Embodiment 21. The apparatus of any one of embodiments 14 to 20, whereinthe heat exchanger is in fluid communication with the first and secondoxidant-containing gas inlet chambers.

Embodiment 22. The apparatus of any one of embodiments 1 to 21, whereinthe heat exchanger comprises a serpentine shape.

Embodiment 23. The apparatus of any one of embodiments 1 to 22, whereinthe heat exchanger comprises a fin, a baffle, or a combination thereof.

Embodiment 24. The apparatus of any one of embodiments 1 to 23, whereinthe heat exchanger comprises a material having an emissivity of at least0.90 or at least 0.95.

Embodiment 25. The apparatus of any one of embodiments 13 to 24, furthercomprising a second heat exchanger disposed in the first fuel gas outletchamber.

Embodiment 26. The apparatus of embodiment 25, further comprising athird heat exchanger disposed in the second fuel gas outlet chamber.

Embodiment 27. The apparatus of embodiment 25 or 26, wherein the secondheat exchanger, the third heat exchanger, or both comprises a reformer,a vaporizer, or a combination thereof.

Embodiment 28. The apparatus of any one of embodiments 25 to 27, whereinthe second heat exchanger is in fluid communication with at least one orat least two of the first, second, third, and fourth electrochemicaldevices.

Embodiment 29. The apparatus of any one of embodiments 25 to 28, whereinthe third heat exchanger is in fluid communication with at least one orat least two of the first, second, third, and fourth electrochemicaldevices.

Embodiment 30. The apparatus of any one of embodiments 1 to 29, furthercomprising:

a first fuel gas inlet chamber in fluid communication with the firstelectrochemical device;

a second fuel gas inlet chamber in fluid communication with the secondelectrochemical device;

a third fuel gas inlet chamber in fluid communication with the thirdelectrochemical device; and

a fourth fuel gas inlet chamber in fluid communication with the fourthelectrochemical device.

Embodiment 31. The apparatus of embodiment 30, wherein the second heatexchanger is in fluid communication with two of the fuel gas inletchambers and the third heat exchanger is in fluid communication with theother two of the gas inlet chambers.

Embodiment 32. The apparatus of any one of embodiments 1 to 31, furthercomprising:

a fuel gas inlet manifold attached to at least one electrochemicaldevice;a fuel gas outlet manifold attached to at least two electrochemicaldevices; orany combination thereof.

Embodiment 33. The apparatus of any one of embodiments 30 to 32, whereineach fuel gas inlet chamber is contained by a fuel gas inlet manifold.

Embodiment 34. The apparatus of any one of embodiments 30 to 33, whereineach fuel gas outlet chamber is contained by a fuel gas outlet manifold.

Embodiment 35. The apparatus of any one of embodiments 32 to 34, whereina reformer, a vaporizer, or a combination thereof is disposed within awall of the fuel gas outlet manifold.

Embodiment 36. The apparatus of any one of embodiments 32 to 35, whereina reformer, a vaporizer, or a combination thereof is disposed withininsulation placed outside of the fuel gas outlet manifold.

Embodiment 37. The apparatus of any one of embodiments 25 to 36, whereinat least one of the second heat exchanger or the third heat exchangercomprises branches extending in different directions, wherein eachbranch is connected to a fuel inlet manifold.

Embodiment 38. The apparatus of any one of embodiments 25 to 37, furthercomprising a fuel gas inlet pipe connected to the second or the thirdheat exchanger and connected to a fuel gas inlet manifold, wherein thefuel gas inlet pipe is in fluid communication with the second or thethird heat exchanger and with the fuel gas inlet chamber contained bythe fuel gas inlet manifold.

Embodiment 39. The apparatus of any one of embodiments 1 to 38, furthercomprising an oxidant-containing gas inlet pipe connected to the heatexchanger and to the oxidant-containing gas inlet chamber, wherein theoxidant-containing gas inlet pipe is in fluid communication with theheat exchanger and the oxidant-containing gas inlet chamber.

Embodiment 40. The apparatus of any one of embodiments 25 to 39, furthercomprising a fuel gas outlet pipe connected to the fuel gas outletmanifold, wherein the fuel gas outlet pipe is in fluid communicationwith the fuel gas outlet chamber contained by the fuel gas outletmanifold.

Embodiment 41. The apparatus of any one of embodiments 25 to 40, furthercomprising an oxidant-containing gas outlet pipe connected to and influid communication with the oxidant-containing gas outlet chamber.

Embodiment 42. The apparatus of any one of embodiments 1 to 41, whereinthe apparatus does not include an oxidant-containing gas inlet manifoldor an oxidant-containing gas outlet manifold.

Embodiment 43. The apparatus of any one of embodiments 1 to 11, furthercomprising:

a first oxidant-containing gas outlet chamber disposed between the firstand second electrochemical devices; and

a second oxidant-containing gas outlet chamber disposed between a thirdand fourth electrochemical devices,

wherein the first oxidant-containing gas outlet chamber is in fluidcommunication with oxidant-containing gas outlet surfaces of the firstand second electrochemical devices; and

wherein the second oxidant-containing gas outlet chamber is in fluidcommunication with oxidant-containing gas outlet surfaces with the thirdand fourth electrochemical devices.

Embodiment 44. The apparatus of embodiment 43, wherein the first,second, third, and fourth electrochemical devices are disposed in onerow.

Embodiment 45. The apparatus of embodiment 43 or 44, further comprisinga fuel gas inlet chamber in fluid communication with at least one, atleast two, or each one of the plurality of electrochemical devices.

Embodiment 46. The apparatus of any one of embodiments 1 to 11 and 43 to45, further comprising a fuel gas outlet chamber opposite the fuel gasinlet chamber, wherein a heat exchanger is disposed within a wall of thehousing adjacent the fuel gas outlet chamber, wherein the heat exchangercomprises a reformer, a vaporizer, or a combination thereof.

Embodiment 47. The apparatus of any one of embodiments 1 to 11 and 43 to45, comprising a fuel gas outlet chamber disposed between at least twoof the plurality of electrochemical devices.

Embodiment 48. The apparatus of any one of embodiments 1 to 11 and 43 to45, comprising a fuel gas outlet chamber disposed between and in fluidcommunication with a fuel gas outlet surface of an electrochemicaldevice and a fuel gas inlet surface of an adjacent electrochemicaldevice.

Embodiment 49. The apparatus of any one of embodiments 1 to 11 and 43 to48, further comprising:

an inlet gas pipe in fluid communication with at least twoelectrochemical devices;

an outlet gas pipe in fluid communication with at least twoelectrochemical devices; or

a combination thereof.

Embodiment 50. The apparatus of embodiment 49, further comprising a gasinlet pipe wherein the inlet gas pipe comprises a first and secondbranches extending toward the respective fuel gas inlet surfaces of theat least two electrochemical devices or toward the respective theoxidant-containing gas inlet surfaces of the at least twoelectrochemical devices, wherein the first and second branches comprisedifferent diameters.

Embodiment 51. The apparatus of embodiment 49 or 50, wherein the inletgas pipe comprises a first and second branches extending toward therespective fuel gas inlet surfaces of the at least two electrochemicaldevices or toward the respective the oxidant-containing gas inletsurfaces of the at least two electrochemical devices, wherein at leastone of the first and second branches comprise a necking extending intothe flow path.

Embodiment 52. The apparatus of any one of embodiments 49 to 51, whereinthe inlet gas pipe comprises a chamber, wherein the first and secondbranches extend away from the chamber.

Embodiment 53. The apparatus of any one of embodiments 49 to 52, whereinthe inlet gas pipe is an oxidant-containing gas inlet pipe connected toand in fluid communication with the heat exchanger and at least oneoxidant-containing gas inlet chamber.

Embodiment 54. The apparatus of any one of embodiments 49 to 53, whereinthe inlet gas pipe is a fuel gas inlet pipe connected to and in fluidcommunication with the second or third heat exchanger and at least onefuel gas inlet chamber.

Embodiment 55. The apparatus of any one of embodiments 49 to 54, furthercomprising a gas outlet pipe, wherein the gas outlet pipe is anoxidant-containing gas outlet pipe comprising first and second branchesconnected to the oxidant-containing gas outlet chamber.

Embodiment 56. The apparatus of any one of embodiments 49 to 55, whereinthe gas outlet pipe is a fuel gas outlet pipe comprising first andsecond branches connected to the first and second fuel gas outletchambers, respectively.

Embodiment 57. The apparatus of any one of embodiments 1 to 56, whereinthe apparatus comprising:

an oxidant-containing gas inlet manifold attached to at least oneelectrochemical device, whereinthe oxidant-containing gas inlet chamber is part of theoxidant-containing gas inlet manifold;an oxidant-containing gas outlet manifold attached to at least oneelectrochemical device,wherein the oxidant-containing gas outlet chamber is part of theoxidant-containing gas outlet manifold;a fuel gas inlet manifold attached to at least one electrochemicaldevice, wherein the fuel gas inlet chamber is part of the fuel gas inletmanifold;a fuel gas outlet manifold attached to at least one electrochemicaldevice, wherein the fuel gas outlet chamber is part of the fuel gasoutlet manifold; orany combination thereof.

Embodiment 58. The apparatus of any one of embodiments 34 to 41 and 56,wherein at least one of the manifolds comprises a recess configured toreceive at least one of the plurality of electrochemical devices.

Embodiment 59. The apparatus of any one of embodiments 56 to 58, whereinthe inlet or outlet gas pipes are connected to the manifolds viawelding, a glass-ceramic seal, or a combination thereof.

Embodiment 60. The apparatus of any one of embodiments 56 to 59,wherein:

the fuel gas outlet manifold comprises a metal;

the fuel gas inlet manifold comprises a ceramic material; or

a combination thereof.

Embodiment 61. The apparatus of any one of embodiments 56 to 60,wherein:

the oxidant-containing gas outlet manifold comprises a metal;

the oxidant-containing gas inlet manifold comprises a ceramic material;or

a combination thereof.

Embodiment 62. The apparatus of any one of embodiments 56 to 61, whereinthe manifolds are attached to the plurality of electrochemical devicesvia compression.

Embodiment 63. The apparatus of embodiment 1 or 2, wherein apparatuscomprises an arrangement including at least two electrochemical devicesalternating with manifolds.

Embodiment 64. The apparatus of embodiment 63, wherein the at least twoelectrochemical devices and at least 3 manifolds are compressed inseries.

Embodiment 65. The apparatus of embodiment 63 or 64, wherein theapparatus comprises a plurality of the arrangements compressed inparallel by a single compression system.

Embodiment 66. The apparatus of any one of embodiments 62 to 65, whereinthe compression is exerted via independent springs, a band, a cable, aratchet, leaf springs, conical spring washers, clamps, weld, or anycombination thereof.

Embodiment 67. The apparatus of any one of embodiments 62 to 66, whereinthe compression is exerted by a compression system external to thehousing, wherein the compression is transferred to the manifold,electrochemical devices, or a combination thereof via an insulationcomponent.

Embodiment 68. The apparatus of any one of embodiments 62 to 67, furthercomprising a gasket placed between an electrochemical device and atleast one of the manifolds.

Embodiment 69. The apparatus of any one of embodiments 1 to 68, whereinthe electrochemical device comprises a stack of solid oxide fuel cells,a battery, or a solid oxide electrolyzer cell.

Embodiment 70. The apparatus of any one of embodiments 1 to 69, whereinthe electrochemical device comprises a stack of solid oxide fuel cellsand the stack of solid oxide fuel cells has a cross-flow configuration.

Embodiment 71. The apparatus of embodiment 70, wherein the stack ofsolid oxide fuel cells consists essentially of ceramic materials.

Embodiment 72. The apparatus of any one of embodiments 35 to 71, whereinthe manifolds are external to the electrochemical devices.

Embodiment 73. An apparatus, comprising:

a housing; and

a plurality of electrochemical devices disposed within the housing,wherein the plurality of electrochemical devices comprise a first andsecond electrochemical devices, and

a first gas outlet chamber within the housing, wherein the gas outletchamber is between and in fluid communication with the first and secondelectrochemical devices.

Embodiment 74. The apparatus of embodiment 73, further comprising afirst heat exchanger disposed within the gas outlet chamber.

Embodiment 75. The apparatus of any one of embodiments 1 to 74, whereinthe plurality of electrochemical devices comprise at least 2, at least4, at least 6, at least 8, or at least 9 electrochemical devices.

Embodiment 76. The apparatus of any one of embodiments 1 to 75, whereinat least one of the electrochemical devices comprises a first gaschannel extending between a second surface and the first surface of theelectrochemical device, the second surface being opposite the firstsurface, wherein the first gas channel comprises a gas outflow end atthe first surface, the gas outflow end facing the heat exchanger.

Embodiment 77. The apparatus of embodiment 76, wherein the heatexchanger is positioned such that a major surface of the heat exchangerfaces the first surface.

Embodiment 78. The apparatus of embodiments 76 or 77, wherein the heatexchanger includes a surface area that is directly exposed to the firstsurface, wherein the surface area is at least 25%, at least 40%, atleast 60%, or at least 75% of a total area of the first surface.

Embodiment 79. The apparatus of any one of embodiments 77 to 78, whereinthe heat exchanger and the electrochemical device are arranged such thatan outlet gas passing through the first surface passes across orimpinges upon the heat exchanger.

Embodiment 80. The apparatus of any one of embodiments 1 to 79, whereinthe heat exchanger is configured to receive and heat an inlet gas thathas a temperature lower than a temperature of the at least one of theplurality of electrochemical devices.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims. Reference herein to a materialincluding one or more components may be interpreted to include at leastone embodiment wherein the material consists essentially of the one ormore components identified. The term “consisting essentially” will beinterpreted to include a composition including those materialsidentified and excluding all other materials except in minority contents(e.g., impurity contents), which do not significantly alter theproperties of the material. Additionally, or in the alternative, incertain non-limiting embodiments, any of the compositions identifiedherein may be essentially free of materials that are not expresslydisclosed. The embodiments herein include range of contents for certaincomponents within a material, and it will be appreciated that thecontents of the components within a given material total 100%.

The specification and illustrations of the embodiments described hereinare intended to provide a general understanding of the structure of thevarious embodiments. The specification and illustrations are notintended to serve as an exhaustive and comprehensive description of allof the elements and features of apparatus and systems that use thestructures or methods described herein. Separate embodiments may also beprovided in combination in a single embodiment, and conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.Further, reference to values stated in ranges includes each and everyvalue within that range. Many other embodiments may be apparent toskilled artisans only after reading this specification. Otherembodiments may be used and derived from the disclosure, such that astructural substitution, logical substitution, or another change may bemade without departing from the scope of the disclosure. Accordingly,the disclosure is to be regarded as illustrative rather thanrestrictive.

What is claimed is:
 1. An apparatus, comprising: a housing; a pluralityof electrochemical devices disposed within the housing; and a heatexchanger disposed within the housing and faced with anoxidant-containing gas outlet surface of at least one of the pluralityof electrochemical devices.
 2. The apparatus of claim 1, wherein theplurality of electrochemical devices comprise a first and secondelectrochemical device, and wherein the heat exchanger is faced with anoxidant-containing gas outlet surface of the first electrochemicaldevice and an oxidant-containing gas outlet surface of the secondelectrochemical device.
 3. The apparatus of claim 2, further comprisingan oxidant-containing gas outlet chamber enclosed in the housing,wherein the oxidant-containing gas outlet chamber is in fluidcommunication with the first and second electrochemical devices, andwherein the heat exchanger is disposed within the oxidant-containing gasoutlet chamber.
 4. The apparatus of claim 3, wherein theoxidant-containing gas outlet chamber is disposed on one side of thefirst and second electrochemical devices.
 5. The apparatus of claim 3,wherein the oxidant-containing gas outlet chamber is disposed betweenthe first and second electrochemical devices.
 6. The apparatus of claim3, wherein the plurality of electrochemical devices are arranged in agrid, and wherein the oxidant-containing gas outlet chamber is a centraloxidant-containing gas outlet chamber in fluid communication with atleast 4 electrochemical devices including the first and secondelectrochemical devices.
 7. The apparatus of claim 3, furthercomprising: a fuel gas outlet chamber disposed between and in fluidcommunication with the first and second electrochemical device.
 8. Theapparatus of claim 3, further comprising: an oxidant-containing gasinlet chamber in fluid communication with the first and secondelectrochemical devices.
 9. The apparatus of claim 3, wherein the heatexchanger comprises a first branch and a second branch extending inopposite directions, wherein the first branch is coupled to a firstoxidant-containing gas inlet chamber in fluid communication with thefirst electrochemical device, and the second branch is coupled to asecond oxidant-containing gas inlet chamber in fluid communication withthe second electrochemical device.
 10. The apparatus of claim 7, furthercomprising a heat exchanger disposed in the fuel gas outlet chamber. 11.The apparatus of claim 10, wherein the heat exchanger disposed in thefuel gas outlet chamber is coupled to a fuel gas inlet chamber in fluidcommunication with at least one of the first and second electrochemicaldevices.
 12. The apparatus of claim 1, wherein the heat exchangercomprises a reformer, a vaporizer, or a combination thereof.
 13. Theapparatus of claim 1, further comprising: a fuel gas inlet manifoldattached to at least one of the plurality of electrochemical devices,wherein the fuel gas inlet manifold contains a fuel gas inlet chamber influid communication with the at least one electrochemical device; a fuelgas outlet manifold attached to at least one of the plurality ofelectrochemical devices, wherein the fuel gas outlet manifold contains afuel gas outlet chamber in fluid communication with the at least oneelectrochemical device; or a combination thereof.
 14. The apparatus ofclaim 13, wherein at least one of the fuel gas inlet and outletmanifolds comprises a recess configured to receive the at least one ofthe plurality of electrochemical devices.
 15. The apparatus of claim 13,wherein the fuel gas inlet and outlet manifolds are attached viacompression.
 16. The apparatus of claim 13, wherein the fuel gas inletand outlet manifolds are external to the plurality of electrochemicaldevices.
 17. The apparatus of claim 1, further comprising: a firstoxidant-containing gas outlet chamber disposed between a firstelectrochemical device and a second electrochemical device of theplurality of electrochemical devices; and a second oxidant-containinggas outlet chamber disposed between a third electrochemical device and afourth electrochemical device of the plurality of electrochemicaldevices, wherein the heat exchanger is disposed within one of the firstand second oxidant-containing gas outlet chambers; wherein the firstoxidant-containing gas outlet chamber is in fluid communication withoxidant-containing gas outlet surfaces of the first and secondelectrochemical devices; and wherein the second oxidant-containing gasoutlet chamber is in fluid communication with oxidant-containing gasoutlet surfaces with the third and fourth electrochemical devices. 18.The apparatus of claim 1, wherein the electrochemical device comprises astack of solid oxide fuel cells, a battery, or a solid oxideelectrolyzer cell.
 19. The apparatus of claim 1, wherein the heatexchanger includes a surface area that is directly exposed to theoxygen-containing gas outlet surface, wherein the surface area is atleast 25% of a total area of the oxygen-containing gas outlet surface.20. The apparatus of claim 1, wherein the at least one of the pluralityof electrochemical devices comprises at least one gas channel extendingbetween the oxygen-containing gas outlet surface and an oppositeoxygen-containing gas inlet surface, wherein the heat exchanger isexposed to a gas outflow end of the at least one gas channel.